A giant Syrian flag is held by the crowd during a protest against President Bashar al-Assad after Friday prayers in the city centre of Hama July 29, 2011. REUTERS/Handout

Syrians in their thousands took to the streets nationwide for the 17th consecutive Friday to demand an end to President Bashar al-Assad’s 11-year rule, activists said by telephone, defying an intensifying military crackdown on an uprising for political freedoms.

“The security forces are continuing violent repression against peaceful demonstrations demanding freedom and the downfall of the regime, firing live ammunition at most protests all over Syria on Friday,” Sawasiah said in a statement sent to Reuters.

Sawasiah said it had the names of 20 people killed in the cities of Latakia, Hama, Homs, Deraa, Kiswa, Deir al-Zor and in and around the capital Damascus.

Syrian authorities have expelled most independent journalists since the uprising began, making it difficult to verify reports of clashes, and do not usually comment on reports of killings.

Arrests continued across the country in the last two days, rights campaigners said, including hundreds of people in Damascus, where they said Republican Guards deployed in force in the central Maidan district on Friday to prevent protests.

The official Syrian news agency said a member of the security police was killed in the town of Albu Kamal on the border with Iraq, and that saboteurs bombed an export oil pipeline near the central city of Homs on Friday,

The attack caused an oil leak, it said. Homs, where the army has deployed tanks, hosts one of Syria’s two oil refineries and has been hit by big street protests.

“Our main goal is the downfall of the regime,” a preacher told worshippers at the central Orontes Square in the city of Hama, scene of a massacre by the military in the 1980s.

Inspired by “Arab Spring” uprisings that toppled veteran leaders in Tunisia and Egypt, popular protests broke out in March against four decades of repressive rule by the Assad family. The unrest is now taking on sectarian overtones, with protesters from the Sunni Muslim majority pitted against minority Alawites who dominate the power elite.

CRACKDOWN IN EASTERN OIL REGION

Military intelligence, in charge of securing loyalty to Assad among the army’s mostly Sunni rank and file, has been spearheading a crackdown in Syria’s Sunni tribal east, a strategic oil-producing region near the border with Iraq.

Many inhabitants of the region have weapons because the government earlier armed eastern tribes, which have close links with Iraq, as a counterweight to Syria’s Kurdish population, much of it in regions adjacent to Deir al-Zor province.

Residents of Deir al-Zor, speaking to Reuters by telephone, reported fighting from the early hours of Friday, with tanks entering the city overnight.

The fighting later subsided but at least a dozen helicopters were seen ferrying troops to a military airport, and tank reinforcements arrived and took positions around the city, residents said.

There have been individual instances of Syrians using weapons during the unrest, for example defending their homes during assaults on restive cities by security forces.

But the fighting reported in Deir al-Zor appeared to represent an armed response by a significant number of people to Assad’s iron-fisted clampdown on public dissent.

On Sunday, Assad replaced the civilian governor of Deir al-Zor province with the head of the country’s main prison, two days after the biggest pro-democracy demonstrations in the province so far.

Last week the army surrounded the town of Albu Kamal on the easternmost edge of Deir al-Zor after 30 soldiers defected following the killing of four protesters, residents said.

Deir al-Zor is the centre of Syria’s daily oil output of 380,000 barrels but is among the poorest of the country’s 13 provinces, afflicted by drought and economic mismanagement.

The Syrian leadership blames “armed terrorist groups” for most killings during the revolt, which began with demands for political liberalisation and now seeks the toppling of Assad, who succeeded his late father, Hafez al-Assad, in 2000.

The global activist group Avaaz said in a new report that Syrian security forces had killed 1,634 people, while at least 2,918 had disappeared in Assad’s violent crackdown. Another 26,000 had been arrested, many of whom were beaten and tortured, and 12,617 remained in detention, it said.

The Syrian government has said more than 500 soldiers and security personnel have been killed. Human rights campaigners say soldiers who have refused to fire on civilians have been shot dead. They add that army conscripts and rank and file members have been defecting in increasing numbers.